ProjectClassLoader leak in executable model compilation of declare types

When compiling a DRL containing declare types with executable model, the ProjectClassLoader associated with the compiled declare types is kept in scope by a couple of static maps:

    org.drools.model.bitmask.BitMaskUtil.accessiblePropertiesCache;
    org.drools.modelcompiler.util.ClassUtil.ACCESSIBLE_PROPS_CACHE;

In turn, this generates a leak of all the resources associated with the ProjectClassLoader (e.g., MemoryFileSystem with all the source content of the kmodule).

We also have a concern on the thread safety of these static maps (as they do not appear to be synchronized). I.e., what happens if multiple kmodules are compiled concurrently by different threads?